It is well known that many personal appliances or small mechanical devices in the form of sexual devices and massage instruments use rotational drive energy or servo drives in the generation of fine movements, such as radial vibration. Conventional masturbation and massage devices typically provide radial vibratory energy, rotational energy or oscillations in two axes. Generally, devices with this type of energy translation exist as a healthy sexual outlet and can be valuable tools in sex-therapy, including enhancement of one's sexual awareness and reduction of fears of intimacy. A large majority of women, in particular, cannot achieve climax without external stimulation. Devices that allow masturbation have the potential to decrease unwanted births and decrease the transmission of sexually transmitted disease, as they can be implemented without a partner. Furthermore, the utility of self-massage devices is well known, as there are many commercially available. Indeed, there exists a multitude of hand held scratching, vibrating and dual-action massagers.
In 2003, an exhaustive analysis of the market for sexual devices was performed as perhaps best described in U.S. Pat. No. 6,902,525 to Jewell. Specifically, a need was identified for sexual devices to provide enhanced personal pleasure for people with all types of sexual dispositions. The most common of these devices currently available is the vibrator or vibrating dildo or vibrating massager. While these types of devices are commonly known and cheaply made, they provide less than optimal stimuli—mostly random and primarily radial impulses.
Typically, the common feature among these devices is a simple unbalanced weight driven by a motor. One of the most popular vibrating massage devices is made by Hitachi, and it is unique in that the weight is supported by bearings in a stimulator section which is distal to the motor and wrapped in a flexible material. This design gives more freedom for the stimulator and protects the motor from radial loads. It was a generous leap forward in terms of massager/stimulator design, but it does not directly create larger amplitude percussive or mechanical slip motions that can activate specialized sensory receptors found in human genitalia.
Histological analysis of the human genitalia supports the relevance of diverse stimuli. The sensory receptors in the human genitalia are unique in distribution and type, even among glabrous (non-hair containing) skin. The human penis contains a large number of free nerve endings, as well as more complex corpuscular receptors. The density and type of receptor affect the types of stimuli that a particular area of skin can perceive and the sensitivities to such. For example, the distal aspect of the penis has poor fine touch sensation when compared to its ability to sense pressure and pain. The foreskin on the other hand, has a larger number of fine touch or specialized corpuscular receptors. These more complex receptors are higher in density around the corona and transition zones between the prepuce and glans. In the female clitoris, similar receptor distributions/types can be found, as the clitoris is embryologically related to the penis.
A variety of adaptation times can be found among the types of sensory receptors in the genital organs. Some possess fast adaptation times that produce a decrease in output with constant stimulation, and some have slow adaptation times. An effective stimulator will maximally activate a range of receptors including the mechano-receptors that increase their output based on the degree of pressure or deformation of the skin as well as the slow adapting receptors that respond to stretch. Enhanced stimulation of the genitalia cannot be accomplished through a simple medium-frequency vibration that creates minimal stretch and displacement of sensory receptors. Many genital mechano-receptors will respond to this through adaptation with a decrease in sensory receptor output over time.
Therefore, there exists a need for a device designed to provide a safe method of effective tactile stimulation that provides additional mechanical stimulation through vibrating, orbiting and torsional (or rotational) oscillations. Furthermore, the device should have the additional benefit of increased stimulation as well as superior massage characteristics by generating slip and additional pressure stimuli. The device should be capable of being used alone or as an implement on other commercially available devices.